What was found
(CAN) UNABLE TO ACHIEVE TAKEOFF POWER, WITHOUT RETURNING AT THE DATE, CREW DID A SUCCESSFUL POWER RUN AND A/C DEPARTED. SAME THING HAPPENED ON THE NEXT LEG. AFTER INVESTIGATION, MAINTENANCE FOUND COUPLING BETWEEN ENGINE AND FRAME FFG CABLE CONNECTOR CONTAMINATED WITH CARBON AND DIRT. CLAMP CLEANED AND RETORQUED. A/C RETURNED TO SERVICE.